Exploring attention-based explanations for some violations of Hick’s law for aimed movements

Choice reaction time generally increases linearly with the logarithm of the number of potential stimulus-response alternatives, a regularity known as Hick's law. Two apparent violations of this generalization, which have been reported for aimed eye movements (Kveraga, Boucher, & Hughes, Experimental Brain Research, 146, 307-314, 2002), and arm movements (Wright, Marino, Belovsky, & Chubb, Experimental Brain Research, 179, 475-496, 2007), occurred when the indicator stimulus was an abrupt change at the location that was the target of the to-be-made movement. We report two experiments that examined and rejected the hypothesis that these abrupt-onset indicator stimuli triggered a shift in exogenous attention and that this led to unusually small uncertainty effects. Each experiment compared this indicator stimulus with a single alternative: Experiment 1 tested an indicator stimulus at all locations other than the target; Experiment 2 tested a central pointer to the target. Neither alternative led to an uncertainty effect for pointing responses that was of the size typically observed for other responses using the same stimuli.     

Parental Problem-Solving Abilities and the Association of Sickle Cell Disease Complications with Health-Related Quality of Life for School-Age Children

Children with sickle cell disease (SCD) are at risk for poor health-related quality of life (HRQOL). The current analysis sought to explore parent problem-solving abilities/skills as a moderator between SCD complications and HRQOL to evaluate applicability to pediatric SCD. At baseline, 83 children ages 6–12 years and their primary caregiver completed measures of child HRQOL. Primary caregivers also completed a measure of social problem-solving. A SCD complications score was computed from medical record review. Parent problem-solving abilities significantly moderated the association of SCD complications with child self-report psychosocial HRQOL (p = .006). SCD complications had a direct effect on parent proxy physical and psychosocial child HRQOL. Enhancing parent problem-solving abilities may be one approach to improve HRQOL for children with high SCD complications; however, modification of parent perceptions of HRQOL may require direct intervention to improve knowledge and skills involved in disease management.     

Strategic and automatic threat processing in chronic musculoskeletal pain: a startle probe investigation

Attentional bias research with chronic pain samples has yielded conflicting results. In the present investigation the startle paradigm was used to test the postulate that fear-based mechanisms play an important role in attentional biases for pain-related threat in chronic pain. Participants, including 31 individuals with chronic musculoskeletal pain and 20 healthy controls, completed a startle task designed to measure attention to different types of words (neutral vs sensory pain vs affective pain vs health catastrophe) presented at different levels of cognitive processing (strategic vs automatic). Measures of fear-based individual difference variables, including anxiety sensitivity and fear of pain, were also completed. Startle amplitudes and latencies to acoustic startle probes that followed word presentations were recorded. Data were analyzed with repeated measures ANOVAs and correlational analysis. Significant between-group differences were found indicating that, relative to chronic pain participants, healthy controls had higher startle amplitude index scores for health catastrophe words. There was also a trend among patients with chronic pain for greater startle amplitude index scores for strategic presentations of sensory pain words. In the automatic condition, all participants demonstrated a lower startle latency index for sensory words relative to both affect and health catastrophe words, suggesting participants had more difficulty disengaging from affect and health catastrophe words or were more avoidant of sensory words. Correlational analyses indicated that startle response indices for words related to health catastrophe became more pronounced for chronic pain patients as anxiety sensitivity and fear of pain increased. Implications and directions for future research are discussed.     

A collaborative approach in the treatment of chronic pain

The impact of chronic pain on patients and their families can be devastating, with significant disruption and progressive deterioration of many life functions and roles. Typically, chronic pain patients have exhausted all standard medical treatment alternatives without finding relief from the pain. For chronic pain patients and their families, this leads to dependency on the health-care system which leaves patients and their families feeling helpless and hopeless in their struggle to survive their pain experiences. Assessment and treatment of chronic pain requires a comprehensive approach based on a multidimensional conceptualisation of pain that addresses cognitive, affective, behavioural, as well as sensory factors in the pain experience. A cognitive-behavioural treatment programme consisting of (a) a comprehensive multidimensional assessment, (b) a reconceptualisation aspect, (c) a skills acquisition phase, (d) a skills application, maintenance, and generalisation component, and (e) relapse prevention, is outlined. Emphasis is given to the important inter-related roles of the collaborative therapeutic relationship, reconceptualisation of the pain experience, and coping skills training, leading to self-management of life with pain as the ultimate treatment objective.     

Affect intensity and cardiac arousal.

Relationships between affect intensity and basal, evoked, and perceived cardiac arousal were investigated in 3 experiments. Affect intensity was assessed using Larsen and Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (Blascovich, 1990).     

Recent research on the relationship between illicit drug use and crime

This article reviews research on the relationship between illicit drug use and crime conducted since 1980. Significant advances are noted in studies of the crime of known drug abusers and in studies of the drug use of individuals processed by the criminal justice system. Major conclusions supported by the results of studies of the criminal activity of narcotic abusers are that both a higher prevalence and higher rates of crime are associated with more frequent use of heroin and/or cocaine, although addicts vary with regard to the type, amount, and severity of crime they commit. Rates of lifetime and recent illicit drug use, particularly the use of cocaine, among prisoners, parolees, probationers, and arrestees are high compared to the general population. Issues discussed include the etiology of drug abuse, the effects of treatment and criminal justice interventions on drug use and crime, and drug-related violence.     

Enhancement of naming in nonfluent aphasia through gesture

In a number of studies that have examined the gestural disturbance in aphasia and the utility of gestural interventions in aphasia therapy, a variable degree of facilitation of verbalization during gestural activity has been reported. The present study examined the effect of different unilateral gestural movements on simultaneous oral-verbal expression, specifically naming to confrontation. It was hypothesized that activation of the phylogenetically older proximal motor system of the hemiplegic right arm in the execution of a communicative but nonrepresentational pointing gesture would have a facilitatory effect on naming ability. Twenty-four aphasic patients, representing five aphasic subtypes, including Broca's, Transcortical Motor, Anomic, Global, and Wernicke's aphasics were assessed under three gesture/naming conditions. The findings indicated that gestures produced through activation of the proximal (shoulder) musculature of the right paralytic limb differentially facilitated naming performance in the nonfluent subgroup, but not in the Wernicke's aphasics. These findings may be explained on the view that functional activation of the archaic proximal motor system of the hemiplegic limb, in the execution of a communicative gesture, permits access to preliminary stages in the formative process of the anterior action microgeny, which ultimately emerges in vocal articulation.     

The role of norepinephrine and acetylcholine in mediating escape deficits produced by inescapable shocks

This study examined the role of neurochemical changes produced by inescapable shock, specifically the depletion of norepinephrine (NE) and enhancement of acetylcholine (ACh), in mediating subsequent inescapable shock-induced deficits in escape acquisition in rats. Enhancement of these neurochemical changes by injections of the NE synthesis inhibitor, FLA-63 (10 mg/kg), or the anticholinesterase, eserine sulphate (3 X 0.5 mg/kg), during the inescapable shock enhanced the subsequent escape deficits observed 3 days later. In contrast, these drugs had no effect on the subsequent escape behavior of rats that were not exposed to inescapable shock. Since these effects could not be attributed to carry-over or state-dependent effects of the drugs, these data suggest that the magnitude of the escape deficit produced by prior inescapable shock is dependent on the magnitude of the initial inescapable shock-induced changes in NE and ACh.